Why do my Azure sites keep going down?

Question

I am testing Microsoft's Azure cloud platform and am hosting two very low-requirement websites. One is a simple single form MVC website that simply accepts some input from the user, performs some calculations, and spits out an output. The second is similar, but it performs a simple query against an Azure SQL Server instance.

Both websites go down constantly. What appears to be happening is that if I don't hit the website for awhile (maybe an hour or so) the GET request simply fails. Nothing is ever returned from the server. If I wait a minute or two and try again, the website works perfectly.

Anyone know what's happening or how I can fix it? I obviously cannot host websites on this platform if the reliability is this low...

Answer 1

Windows Azure Websites used a concept of cold (inactive) and warm (active) sites that means as long as a website has active connection it will be warm or active and after some default time, when the website does not have any active connection it will go in cold or inactive site mode. Once a new connection is established to the same site the site will wake up from inactive (cold) to active (warm) mode and depend on what kind of content needs to be rendered on the website, it may take a few seconds to complete the startup process. The concept of warm and cold sites is described here.

Technically the first GET request will fail if it returns immediately for a cold website however this call does make the site active and next requests will result success.

There was a SO discussion in which the index page had to connect to DB to get the data and because the connection time to DB was longer which resulted the overall start time longer then expected. So there could be several reason by transition from cold to warm may be longer and you can contact Windows Azure Websites team to check why there is the case.